At this summer’s inaugural N-EWN Partner Symposium, we heard talks from partner institutions, organizations and companies from across the country. We also came together to support IRIS affiliates and students as they presented their research on topics from flood modeling to environmental policy.
Below, we’ve compiled the abstracts of IRIS-affiliated presentations from the 2024 N-EWN Partner Symposium to show the breadth of our team’s work. (Read more about the Symposium here!)
Posters
Evaluating the Impacts of Tidal Structures on Infrastructure Performance at Hunter Army Airfield
Ada Agbogu, University of Georgia
Abstract: Coastal communities are threatened by many hazards such as storm surges, flooding, saltwater intrusion, and coastal erosion. These hazards frequently lead to environmental deterioration, property damage, and loss of life. As such, people living around the coasts often use gray infrastructure like seawalls and dikes for protection and shoreline stabilization. However, gray infrastructure often changes the surrounding environment and can prevent natural infrastructure adaptation to changing conditions such as sea level rise. A similar issue has occurred at Hunter Army Airfield Savannah, GA. An installed tide gate led to changes in the marsh vegetation and may substantially affect the utility of the marsh as a natural infrastructure feature. We aim to use field surveys to understand the ecological effects of the tide gate on the surrounding marsh area, and a tidal inundation model (ADCIRC) to quantify how these changes translate to the performance of the marsh ecosystem as a natural infrastructure for flood protection and erosion control. In the future, our research will document the changes in vegetation around the tide gate which will be used to modify the ADCIRC model of the changing landscape conditions. Our findings will help explain the marsh’s performance as a natural infrastructure on the upstream and downstream portions of the tide gate. We will then use our hydrodynamic model to quantify the water surface elevation, and flow velocity across the HAAF tide gate area. These results aim to elucidate issues concerned with tide gate overtopping, potential erosion hotspots, and areas prone to flooding.
Nature-Positive Infrastructure Development: Planning for Multiple Objectives and Design Opportunities in Georgia
Alejandra Gomez, University of Georgia
Abstract: Transportation infrastructure is crucial to economic growth, but it faces challenges from wildlife-vehicle collisions (WVCs) that impact both biodiversity and safety. In the context of climate change and biodiversity loss, a paradigm shift is prompting infrastructure stakeholders to not only prevent damage but also actively promote nature. This includes integrating nature and biodiversity considerations as part of project design or accompanying it with substantial ecological restoration and enhancement efforts. Holistic mitigation strategies are necessary due to the economic and life costs of WVCs. One potential solution is converting culverts into underpasses to reduce WVC occurrences while addressing water and debris conveyance, road safety, ecosystem connectivity, and wildlife conservation. Our study investigates the benefits of innovative culvert design in averting climate change, advancing safety, and promoting ecological connections. Additionally, it targets exact locations in Georgia for optimal culvert upgrades.
Utilizing a watershed-scale approach, our team created a spatial prioritization framework that identifies optimal areas in Georgia for reducing wildlife-vehicle collisions (WVC). This framework takes into account landscape variables that affect WVC frequency and mitigation, improving terrestrial underpasses with culverts, by using a series of metrics such as flood vulnerability assessment, culvert condition and stream channel stability. Utilizing spatial Multi-Criteria Decision Analysis (MCDA), we localize areas in Georgia that combine WVC reduction with ecological and engineering benefits.
Our findings introduce a spatial framework that enables multi-stakeholder assessments for mitigating WVC. This framework prioritizes the maintenance or replacement of hydraulic structures. Additionally, we provide an MCDA tool that allows stakeholders to weigh variable criteria and suggest designs and adaptations for hydraulic structures.
Green Solutions for Gray Spaces: A Case Study of the Tietê River in São Paulo City, Brazil Infrastructure Planning
Luciana Iannone Tarcha, University of Georgia
Abstract: Floods have been part of São Paulo City dynamics since the early human interventions. The 1929 flood of the Tietê River is considered the greatest that has ever hit the city, and yet, 90 years later, São Paulo still suffers from significant floods and water contamination. These are consequences of intense and disordered urbanization, a phenomenon that took place is many other Latin American cities. Over the years, a variety of projects and initiatives were made to manage flood hazards and water quality issues of the Tietê. However, apart from gray infrastructure and superficial green approaches, the concept of Natural and Nature-Based Solutions (NNBS) as a potential solution has not yet been studied nor applied in this system. This study aims to determine how these features can be applied to densely urbanized river floodplains to develop efficient, sustainable, and resilient systems. First, a hydrodynamic model was developed for the study area that includes surface runoff, stream flow, and storm sewer. Then, the proposed infrastructure features were introduced into the model to assess their efficiency. A combination of multiple environmental forcings, such as precipitation, storm flow, and illegal sewer discharge, was considered. Finally, a multicriteria decision analysis determined the best combination of solutions. Latin American people face many challenges related to both past and recent political, economic, and social mismanagement. As the world is an extensive and complex system, it is time to share knowledge so that we can transform it into a resilient and sustainable one.
A Spatial Conservation Prioritization of Coastal Freshwater Impoundments Based on Predicted Climate Impacts and Waterfowl Habitat Value
Alexa Ouellette, University of Georgia
Abstract: Along the southeast Atlantic coast, impoundments have been created to enhance freshwater wetland habitat for migrating and wintering waterfowl. These freshwater impoundments were constructed by clearing all woody vegetation and constructing exterior and interior levees, or “dikes,” and controlling water and salinity levels using water control structures, or “trunks.” In recent years, these impoundments have begun to face issues relating to dike overtopping and salinization by outside water sources (e.g., tidal water and rivers), often due to tropical weather systems. Under current climate and sea-level rise projections, these sites will become increasingly vulnerable to these threats, subsequently increasing the frequency and cost of repairs. Without the conservation of these tidal freshwater systems, freshwater habitat for waterfowl and shorebirds in coastal areas could decline significantly in the future. With limited financial resources to support the increasing cost of maintenance and repair, identifying areas of greatest vulnerability relative to habitat value provided is critical. Omnidirectional connectivity models will be constructed to determine the relative value of waterfowl habitat for eight ecologically and recreationally significant waterfowl species across the landscape. The goal of this project is to create a conservation prioritization tool to better guide future management decisions that trade off vulnerability to damage/loss from sea level rise and storm surge with waterfowl habitat value across the landscape.
Re-Imagining Infrastructure for a Biodiverse Future
Charles van Rees and Seth Wenger, University of Georgia
Abstract: Civil infrastructure will be essential to face the interlinked existential threats of climate change and rising resource demands while ensuring a livable Anthropocene for all However, conventional infrastructure planning largely neglects the contributions and maintenance of Earth’s ecological life support systems, which provide irreplaceable services supporting human well-being. Furthermore, infrastructure development and biodiversity conservation are often planned and executed in isolation, despite the interdependence of contributions to solving sustainability challenges. Here, we envision a new infrastructure paradigm wherein biodiversity and ecosystem services are a central objective of civil engineering. In particular, we reimagine infrastructure practice such that 1) ecosystem integrity and species conservation are explicit objectives from the outset of project planning; 2) infrastructure practices integrate biodiversity into diverse project portfolios along a spectrum from conventional to nature-based solutions and natural habitats; 3) ecosystem functions reinforce and enhance the performance and lifespan of infrastructure assets; and 4) civil engineering promotes environmental justice by counteracting legacies of social inequity in infrastructure development and nature conservation. This vision calls for a fundamental rethinking of the standards, practices, and mission of infrastructure development agencies and a broadening of scope for conservation science. We critically examine the legal and professional precedents for this paradigm shift, as well as the moral and economic imperatives for manifesting equitable infrastructure planning that mainstreams biodiversity and nature’s benefits to people. Finally, we set an applied research agenda for supporting this vision and highlight financial, professional, and policy pathways for achieving it.
Comparative Analysis of Estimated Longshore Sediment Transport Rates with River and Dredging Fluxes in the Savannah Harbor
Oscar Villegas, University of Georgia
Abstract: Understanding the relative contributions of inland and marine sediment sources in estuaries is crucial for predicting and managing sedimentation in harbors. Among various oceanographic factors such as winds, tides, and currents, near-shore waves play a significant role in coastal geomorphology, generating sediment transport along the surf zone through longshore current generated by breaking waves.
In the context of the Georgia Bight, net longshore sediment transport is pivotal for beach dynamics, with islands relying on transport from north to south. However, interpreting the predominant longshore sediment transport direction becomes challenging due to the coexistence of tidal processes, shaping the coast in conjunction with longshore processes. Prevailing southward sediment transport direction has been observed in generalized field studies, often interspersed with local reversals.
The US Army Corps of Engineers has persistently dredged the Savannah River since the 19th century to facilitate the passage of larger container ships. In 2020, annual dredging in Savannah Harbor reached 7.1 million cubic yards, with an estimated 4% of dredged material managed using Regional Sediment Management principles. A two-dimensional hydrodynamic model was employed to understand sediment dynamics in the Savannah Harbor Channel during typical conditions, emphasizing the interplay between hydrodynamics and sediment transport coupled with a wave model. Predominant currents and sediment transport were integrated to elucidate sediment dynamic patterns. The results were compared with estimated total sediment annual discharges and dredge records provided by the Savannah District. These offered valuable insight for effective sediment management and potential beneficial use project implementation.
Quantifying the Increasing Flood Risks Produced by Legacy Levee Systems
Elissa Yeates, University of Georgia
Abstract: Legacy levee systems have associated residual flood risk, which grows over time through layered processes of development, changing climate, and infrastructure aging. Recent work to quantify the effect of levee systems on inducing development in protected floodplains has shown a 50-60% increase in exposure in the event of levee failure, compared with the pre-levee floodplain. Efforts to assess the distribution of this risk across vulnerable populations in the United States have found that non-white and low-income groups are disproportionately living in levee-protected floodplains which, as in the recent Pajaro flooding event, may be insufficiently maintained over time. As population pressures increase floodplain development and climate change increases the likelihood of flood events that exceed system design criteria, this residual risk profile grows.
Strategies to mitigate increasing risks of flooding include hardening built infrastructure systems (such as repairing, maintaining, and raising levees), which can have the effect of worsening downstream flooding potential by increasing riverine flow velocities and scour and inhibiting the function of natural floodplains to attenuate flow. Alternatively, levee systems can be set back, allowing for increased “room for the river” to restore natural floodplain function and increase capacity to attenuate higher flows. We develop a framework to integrate economic and engineering models of risk with SETS theory to determine the scale of the current risk produced by levee systems in the United States. This can guide decision-making on where and when to shift away from hardening traditional levee systems toward strategies of floodplain restoration and levee set-back, considering the hazard, exposure, and vulnerability framework of risk under a shifting climate. Questions considered include: What is the magnitude and distribution of the risk posed by flooding under legacy levee systems? Where and when does investment in system transformation become a favored strategy for mitigating this risk? How can concepts of risk hazard, exposure, and vulnerability be applied to decision-making about levee removal or setback at scale?

Talks
Legal and Social Components of Nature-based Solutions: The Example of Levee Setbacks
Yee Huang & Katie Foster, University of Georgia
Track 1A: NbS Policy and Planning
Abstract: This talk will discuss the legal and regulatory considerations for implementing nature-based solutions through the federal civil works process, focusing specifically on the example of a levee setback. Repeated and catastrophic levee failures, evolving public values, and increasing frequency of extreme weather events have driven the search for better ways to manage flood risk, to repair flood-damaged levees, and to meet environmental and ecosystem needs.
A levee setback is a nature-based solution (NbS) that addresses these goals by improving flood protection and reestablishing historical floodplains. However, the legal and regulatory landscape to implement a setback is evolving and raises social and equity concerns that complicate the decision-making process in infrastructure investments. One particularly complex issue is how to, and with what funding, voluntarily acquire property in the historical floodplain.
For a community interested in implementing a setback, understanding and preparing in advance are critical. This talk will cover specific laws that allow or encourage levee setbacks, how the federal suite of environmental laws specifically apply to levee setbacks, what federal funding is available to support levee setbacks, and lessons learned from using federal funds to voluntarily acquire floodplain properties.
This talk is based on an IRIS in Focus primer written by UGA legal researchers Yee Huang and Matthew Shudtz and subsequent investigations of the complex social issues related to voluntary purchases of floodplain property.
Developing a numerical model to predict the nutrient removal from borrow pits wetlands in the middle Missouri River Basin
Mohamed Gaballah, University of Georgia
Track 1B: Wetlands
Abstract: The U.S. Army Corps of Engineers (USACE), in collaboration with local partners, constructs and maintains an extensive levee network along U.S. rivers, including the lower Missouri. During the repair, maintenance, or realignment of these levees, substantial amounts of fill material are sourced locally from “borrow pits”. Some of these borrow pits have been transformed into wetlands to improve habitat conditions. Notably, certain agricultural drainage ditches have been redirected through these newly created wetlands to enhance water quality, primarily by removing nutrients, before discharge into the Missouri River. Presently, these wetlands are not specifically designed for nutrient retention, and the water quality benefits derived from this practice have not been quantified. The objective of this research is to assess the potential water quality improvements associated with rerouting agricultural drainage through the established constructed wetlands in the lower Missouri River basin. The aim is to contribute to the enhancement of the design of these nature-based solutions. Consequently, a monitoring program focusing on the hydrology and water quality of these borrow pits is being implemented. The intention is to develop and calibrate a numerical model that can assess various design alternatives, offering recommendations to optimize nutrient removal within these wetlands. Additionally, the feasibility of extending these wetlands along the river for the same purpose will be investigated. The outcomes of this study will assist USACE in prioritizing locations for constructed wetlands and refining their design to maximize water quality benefits.
Short burps, tall trees: Trajectories of landscape carbon balance after dam removal
Laura Naslund, University of Georgia
Track 1C: Engineering With Nature and Rivers
Abstract: Dams can facilitate high emissions of carbon dioxide and methane from their reservoirs by flooding terrestrial soils and concentrating organic matter under hypoxic conditions. Dam removal has been proposed as a strategy to reduce emissions while restoring aquatic ecosystems; however, the carbon balance of formerly impounded landscapes depends on multiple pathways of gas exchange. For example, buried organic matter can be rapidly mineralized when exposed to air after reservoir drawdown (resulting in ‘burps’ of carbon emissions), but newly forming terrestrial vegetation and soils in the reservoir footprint can store carbon. The relative contribution of these and other pathways of carbon emissions and storage following dam removal, and thus, the viability of dam removal as a natural climate solution, is unknown. We combine empirical models of surface gas exchange, reservoir sedimentation, and forest regeneration to estimate and characterize the uncertainty in relevant carbon fluxes before, during, and after dam removal. We apply this model to completed dam removals on the Elwha River, WA and the Penobscot River, ME. We find that the fate of previously inundated reservoir sediments is a major determinant of the magnitude and dominant pathways of carbon emissions during dam removal. Regrowing vegetation can eventually offset carbon emissions during dam removal and compensate for lost carbon storage with reduced sediment burial; however, the time to reach this compensation point after dam removal depends greatly on reservoir, dam, and basin characteristics, suggesting that removal of some, but not all, dams may be a beneficial climate solution.
Quantifying the impacts of future shoreline modification on biodiversity
Daniel Coleman, University of Georgia
Track 2A: Biodiversity Panel and Lightning Talks
Abstract: People often modify the shoreline to mitigate erosion and protect property from storm impacts. The two main approaches to modification are gray infrastructure (e.g. bulkheads and seawalls) and natural or green infrastructure (NI; e.g., living shorelines). Gray infrastructure is still more often employed for coastal protection than NI, despite having more detrimental effects on ecosystem parameters, such as biodiversity. Here we assess the impact of gray infrastructure and whether or not the adoption of NI can mitigate losses in biodiversity. We first analyze existing literature to quantify the relationship of both gray infrastructure and NI to biodiversity. We then developed a model using temporal geospatial data on ecosystem distribution and shoreline modification to project future shoreline modification for our study location, coastal Georgia, USA. Finally, we applied the literature-derived empirical relationships of infrastructure effects on biodiversity to the shoreline modification projections to predict change in biodiversity under different NI vs gray infrastructure scenarios. We found that if approximately 40% of all new coastal infrastructure were to be NI, previous losses of biodiversity from gray infrastructure could be mitigated by 2100. As biodiversity continues to decline from human impacts, it is increasingly imperative to minimize negative impacts when possible. We therefore suggest changes to policy and the permitting process to promote the adoption of NI.
Sediment Budgeting to Support Beneficial Use Planning and Sustainability Assessment
C. Rhett Jackson, University of Georgia
Track 2B: Marshes, Living Shorelines, and Sediments
Abstract: Sediment has been called the currency of coastal resilience. Material that is dredged to maintain the navigability of ports and waterways can be strategically placed to create natural infrastructure, such as beaches, dunes, habitat islands, and marshes. However, efficient use of sediment at a regional scale requires data on the volume, grain size, and contamination status of sediment sources in addition to the volume and grain size needs of potential natural infrastructure projects. Using the Savannah District of the United States Army Corps of Engineers as a case study for matching sediment supplies and demands, we are developing a sediment budget that includes river loads, annual dredging quantities, sediment stored in containment facilities, offshore sand deposits, and tidal, wave, and current transport. We have also estimated and compiled expected regional sediment volume needs for beneficial use projects. We will review the uncertainties in the budget and evaluate the long-term sustainability of coastal natural infrastructure enhancement with respect to sediment needs and availability.
Economic Value of Green Infrastructure Investments on the Georgia Coast
Craig Landry, University of Georgia
Track 2C: BCA and Economics
Abstract: Using survey data from the Coastal Empire region of Georgia (Chatham, Bryan, and Liberty Counties, including the city of Savannah), we assess respondents’ perceptions of climate change, sea level rise, and flood & erosion risk, and estimate support and willingness to pay (WTP) for coastal infrastructure approaches to manage climate risk, as well as the value of ecological services provided by infrastructure. A choice experiment is used to assess preferences for green, grey, and hybrid infrastructure investments along water ways in Coastal Empire. An existing policy tool, Special Purpose Local Options Sales Tax (SPLOST), is used as the payment/provision vehicle to enhance realism of the valuation exercise, and the choice experiment is designed to incorporate differential levels of service provision across infrastructure types (e.g., grey exhibits better performance levels for flood protection, while green is superior for habitat provision). We estimate Conditional Logit and Equality-Constrained Latent Class choice models; information criteria support the latter, which controls for attribute non-attendance. Results indicate that green options are the most preferred, followed by hybrid, and grey designs. Economic value estimates indicate MWTP of $17 per household for a one percentage point decrease in the likelihood of severe flooding in low-lying areas over the next 30 years, and MWTP of $6 for a one-day decrease in nuisance flooding. Total household WTP measures for coastal infrastructure projects that deliver the greatest level of environmental services are $154 for grey infrastructure (10% chance of flooding in low-lying areas; 10 days of nuisance flooding per year; and good wildlife habitat), $293 for green infrastructure (30% chance of flooding in low-lying areas; 30 days of nuisance flooding per year; and the best level of wildlife habitat), and $324 for hybrid infrastructure (10% chance of flooding in low-lying areas; 10 days of nuisance flooding per year; and the best level of wildlife habitat).
Compound Flood Modeling for Coastal Military Defense Communities
Lina Cardenas Caro, University of Georgia
Track 5C: Flood Modeling
Abstract: Coastal flood hazards have become a topic of concern due to their increasing occurrence worldwide. Assessing coastal hazards for present and future scenarios under climate change and land use is a foundational step for flood risk. This research aims to develop a compound flood risk assessment focused on military installations and their surrounding communities. The methodology is being developed and tested for the Fort Stewart military installation and adjacent communities, which includes Savannah, GA. The first stage of this research developed a rapid flood risk assessment methodology using a GIS approach, which considered social vulnerability, flood exposure, and critical infrastructure data from open data sources. Results from the rapid flood risk assessment showed the sensitivity of the flood hazard since there was a notorious change in flood risk between the assessments using FEMA flood zones and SACS (South Atlantic Coastal Study) data. For example, the study area’s 2,600 miles of road network changed from low to high flood risk using the FEMA and the SACS data, respectively. This shows the relevance of improving flood hazard data for more accurate flood risk results. Despite the current availability of flood hazard data (e.g., FEMA 100-yr floodplain), data accounting for compound flooding still needs to be provided. Therefore, our ongoing research is focused on developing a framework for the simulation of compound floods, studying the hydrodynamics in the transition zone, and how this will lead to more accurate flood risk assessments.
Modeling the Service Potential of Green Stormwater Infrastructure in Urban Coastal Communities
Matt Chambers, University of Georgia
Track 5C: Flood Modeling
Abstract: Urban green stormwater infrastructure (GSI) has become popular for its ability to provide a wide range of ecosystem services in addition to flood risk management. However, recent literature has questioned the efficacy of GSI in coastal communities exposed to rising groundwater tables from sea-level rise and overloading by compound flooding from multiple flood hazards. In this work, we use a numerical hydrodynamic model to quantify the service of individual GSI (and their combination as systems) under multiple compounding flood hazards, as well as their sensitivity to fluctuations in groundwater levels. Our two-dimensional numerical model (ICPR platform) is capable of propagating coastal processes (e.g., storm surge and astronomical tides), and estimating hydrologic processes (e.g., infiltration, rainfall-runoff, and initial abstractions) simultaneously with dynamic surface to groundwater interchange, thus, allowing us to model the efficacy of GSI under the kinds of hazards coastal communities may face with climate change. Our modeling framework was tested with a barrier island community in Georgia, which enables us to explore the dynamics of interfacing GSI with conventional stormwater infrastructure and practical constraints, such as, where GSI can be placed spatially and underground storage capacity. Furthermore, groundwater and climatologic data are being collected throughout the island and are being used to update and refined the accuracy of our modeling. The utility of this research is advances in numerical modeling techniques for quantifying the service potential of GSI in the face of non-stationary and uncertain future flood hazards driven by anthropogenic climate change.
Combining Riverine and Coastal Natural Infrastructure for Reducing Compound Flood in Estuary Systems
Felix Santiago-Collazo, University of Georgia
Track 5C: Flood Modeling
Abstract: As the world moves towards resilient and safe solutions against natural disasters and climate change, numerical modeling of Natural and Nature-based Features (NNBF)—or even hybrid systems—has been a beneficial approach in recent years. It is vital to analyze these features holistically for estuarine regions to understand and predict their behavior under compound flood events comprising coastal and riverine interactions. However, modeling these features can be challenging, especially if complex numerical models and large amounts of detailed data are required to achieve accurate results. Thus, this project aims to determine the optimum combination of riverine and coastal NNBFs to reduce compound flood impacts from tropical cyclones (TC) in estuarine communities. First, a land-to-ocean characterization will be made for several estuarine systems within the Gulf of Mexico and US Southeast coastline. This will allow us to understand the coastal watershed characteristics within the different regions to create idealized two-dimensional coastal watershed domains that will be used as a testbed for a robust compound flood model. The compound model consists of the ADCIRC model as the main modeling framework, and it will be coupled with a hydrologic model that will quantify the riverine flow conditions. This framework will be subject to several synthetic TC producing extreme wind and rainfall events in close succession. As the world is increasingly concerned about the accuracy of natural hazard predictions and preparedness, it is essential to have less demanding compound models that can be applied to several situations without losing their accuracy and reliability.
Toward Mainstreaming Nature-based Solutions in Federal Flood Management Infrastructure by Improving the Accounting of Benefits in Investment Decision-making Tools
Matt Chambers, University of Georgia
Track 6A: Flood Planning
Abstract: A critical barrier to mainstreaming nature-based solutions (NbS) in the United States are the institutional practices by which the US Army Corps of Engineers (USACE) manages decision-making in infrastructure investments. USACE’s primary quantitative tool is a simple form of benefit-cost analysis (BCA), that at present, has limited accounting for ecosystem services – both market and non-market – and does not accurately account for the spatial and temporal scales over which services may be realized. Recent literature has explored the ecosystem service potential of NbS and developed numerous turn-key tools to catalog and valuate hypothetical services. However, such approaches are data intensive, while site-specific data is often limited, and many hypothetical services (e.g., carbon sequestration and storage) may have low monetary values relative to core services in infrastructure systems designed to, for example, mitigate flooding or support a water supply. In this work, we use the example of a large-scale levee setback on the Missouri River to contextualize ecosystem service valuation and identify the most salient services capable of “moving the needle” in BCA. We then demonstrate simple and repeatable methods for quantifying benefits transfer while defining the spatial and temporal scales practitioners at agencies like USACE will need to accurately account for services in BCA. The utility of this work is the translation of NbS research to practice through refinement of the existing institutional tools USACE uses to plan and justify infrastructure investments.

Panels
Biodiversity
Seth Wenger, Matt Shudtz, Katie Foster
Abstract: As Nature-based Solutions and Natural Infrastructure (hereafter NbS) are increasingly recognized and prioritized as strategies to mitigate and adapt to the impacts of climate change on human societies, many scholars and policymakers cite their potential environmental benefits as a key advantage. The notion that NbS are a “win-win” for both humans and the environment remains insufficiently explored and merits strategic research and planning to increase the likelihood that ecological gains are part of their mainstream implementation. This panel convenes experts working on biodiversity conservation and NbS implementation across different systems and sectors to discuss and highlight opportunities for leveraging NbS development for ecological restoration and achieving biodiversity conservation goals. Panelists will present on topics like benefit quantification for strategic infrastructure planning and corporate sustainability, ecological restoration and monitoring within NbS projects, promoting social justice via nature positive NbS, and legal mechanisms for enhancing biodiversity through NbS development.
Progress Report: Multi-jurisdictional Research on Regulatory Best Practices to Promote Engineering With Nature
Matt Shudtz, Michelle Covi, Yee Huang
CZMA and EFH and 404, oh my! Environmental laws that were designed decades ago to avoid or minimize the adverse impacts of commercial development can create challenges to efficient implementation of EWN projects. As interest in– and funding for– EWN-type projects grows, both project development teams and regulatory agencies are looking for ways to improve the way projects are reviewed and permitted under a variety of federal and state laws. N-EWN partners have been conducting desktop research and interviewing practitioners and government officials to identify the best practices for moving projects through the regulatory and permitting process.
In this session, researchers will share insights from their ongoing research and discuss the opportunities for streamlining regulatory and permitting processes.
Key topics include: the utility (and limits) of Clean Water Act § 404 general permits; the impact of protected species and habitats on project design and implementation; comparative analysis of state laws/regulations; comparative analysis of federal agencies’ regional/district-level approaches; discussion of NBS-specific challenges.
Integrating Agriculture to Advance the Next Frontier of Engineering With Nature
Todd Bridges, Brian Bledsoe
Abstract: The proposed panel will be a discussion on how to advance engineering with nature through integrations with agricultural ecosystems. In practice, this is already being done, but more coordinated efforts and guidance are needed to scale up engineering with nature in agricultural ecosystems. Question and answer discussion will be focused on existing EWN projects integrated with agriculture, as well as forward-thinking needs for the community.
Identifying and Overcoming Obstacles to the Implementation of Natural Infrastructure for Shoreline Modification
Daniel Coleman, Craig Landry, Brock Woodson
Abstract: Shoreline modification, the practice of altering natural coastlines to protect against erosion and other hazards, is expected to become more prevalent with climate change. Shoreline modification is often achieved via living shorelines (a type of Natural Infrastructure; NI) or armoring (gray infrastructure). Living shorelines have been shown to be far less detrimental to natural ecosystems when compared to traditional gray infrastructure (Gittman et al. 2016; Coleman et al. abstract submitted to symposium). This more environmentally friendly approach has piqued the interest of many coastal communities, as well. Despite scientific evidence and growing community support, the adoption of NI for coastal protection is still limited in the United States and other parts of the world. For example, in Georgia, less than 1% of shoreline modification is living shorelines (Georgia Department of Natural Resources 2013). For many, it remains unclear what factors are responsible for the scarcity of NI along the coastline.
This panel aims to address the existing difficulties with implementing NI for coastal protection and how these difficulties can be overcome. We will address this issue from legal, economic, engineering, and manager perspectives. While research continues into the feasibility, design, and performance of NI (Bliss, et al. 2014; Bugbee 2020), many regulators and property owners have been concerned about unknown or unproven effects (Smith, et al. 2020). Engineers and practitioners lack the clear design standards and specifications for NI that are readily available for gray infrastructure. In many US states, including GA, it is more difficult to obtain a permit for NI relative to conventional hard armoring (Jones and Pippin 2022). The panel members will discuss the intricacies of these factors, as well as other complicating factors. We will conclude the panel with a Q+A and/or Open Discussion about the next steps that can be taken to address the discussed issues.
The goals of the panel are:
- Elucidate to researchers why application appears to be lagging behind the state of the science.
- Promote the development of design standards by connecting researchers and engineers.
- Offer tips and guidance for people proposing coastal NI and those responsible for reviewing and permitting such proposals.
- Facilitate transdisciplinary collaborations for the further adoption of coastal NI.
- Inspire experts to make advancements in their respective specialties.
Hydrodynamic Modeling to Support Nature-based Solutions in the Coastal Zone
Matthew Bilskie, Aditya Gupta, Brock Woodson
This session will highlight activities on using coastal numerical and sediment transport models to aid in the feasibility, design, implementation, and performance assessment of NbS. The session will discuss modeling improvements necessary for NbS design and implementation across large scales for wave and water level attenuation.
Session Topics:
- Inclusion of nature-based solutions within numerical models (spatial discretization, vegetation characteristics, etc.)
- Numerical model outputs to inform of NbS strategies, types, and scales for wave and water level attenuation
- Numerical model outputs for project prioritization
- Numerical model outputs to inform engineering design guidance
- Modeling improvements and future needs for NbS